Adjustable riser for sprinkler systems



Feb. 20, 1968 w. .1. TRICKEY ADJUSTABLE RISER FOR SPRINKLER SYSTEMS Filed May 5, 1965 FIG. 2

IN VENTOR WILL IAM J. TRICKEY .f ATTORNEYS United States Patent Oice Patented Feb. 20, 1968 3,369,828 ADJUSTABLE RISER FOR SPRINKLER SYSTEMS William J. Trickey, East Lansing, Mich., assigner to Mahagony Corporation, Williamston, Mich., a corporation of Michigan Filed May 3, 1965, Ser. No. 452,695 2 Claims. (Cl. 285 119) This invention relates generally to water sprinkler systems and in particular to a riser assembly for such systems that is adjustable in height.

In a lawn sprinkler system, water supply pipes are installed below the lawn surface and connected' to sprinkler heads by a vertical riser. With various types of sprinkler heads, as well as couplings into which a sprinkler head can be inserted, it is desirable that the sprinkler head or the coupling be disposed flush with the ground. One type of riser is vertically adjustable to simplify installing sprinkler heads where the depth of the supply pipe varies. One such adjustable riser is disclosed in United States Patent No. 3,084,869, granted April 9, 1963, in the name of Fred A. Hutty et al. The riser disclosed in the Hutty et al. patent can be easily adjusted at any time subsequent to installation of the sprinkler system to compensate for settling, accumulation of cut grass, yand other surface contour changes.

In the riser disclosed in the Hutty et al. patent, the sprinkler head is attached to an upper tubular section which is telescopic in a lower tubular section connected to a water supply pipe. The lower end of the upper section carries a seal that can be expanded radially into engagement with the inner wall of the lower section to serve as a seal and also lock the sections in selected positions of vertical adjustment. In general the seal comprises a nut keyed in the lower section for axial and nonrotatable movement. A -packing ring is disposed above the nut with a washer disposed therebetween. A second washer rests on top of the packing ring. The lower end of the upper section extends through the upper washer and the packing ring, fitting closely in the ring, and is threaded in the nut. When the upper section is screwed downwardly through the nut a radial shoulder on the lower end of the upper section engages the upper washer to compress the packing ring axially causing the ring to expand radially. This arrangement of the seal provides a very satisfactory riser. However, occasionally the upper section may be unthreaded from the nut inadvertently and withdrawn from engagement with the packing ring, particularly when someone unacquainted' with the construction of the riser attempts to adjust its height. If the upper section is unscrewed completely from the nut and disengaged from the packing ring it is diicult, if not impossible, to insert the lower end of the upper section through the ring and into the nut without disassembling the riser. In part this problem is caused because component parts of the seal can cock or cant in the lower section. A close t between the packing ring and the lower end of the upper section also contributes to the problem. Moreover the nut may even drop to the bottom of the riser. It is particularly desirable to minimize this problem or eliminate it completely in risers that are sold' to home owners who install the system themselves and who adjust the riser subsequent to the installation of the system.

The objects of this invention are to provide an adjustable riser that is constructed simply and economically; that can be adjusted simply while maintaining an effective seal at selected positions of adjustment; that minimizes entry of dirt and other foreign matter into the riser during adjustment; and that eliminates the labove-described problem by assuring that the upper section can be reengaged with a locking seal in a simple, easy, and effective manner without disassembling the riser.

Further objects, features and advantages of this invention will become apparent from a consideration of the following description, the appended claims, and the accompanying drawing in which:

FIGURE 1 is a View partly in vertical section of a riser constructed in accordance with the present invention as it appears after installation in the ground' with .a seal on the lower end of the upper section expanded tightly into radial engagement with the lower section of the riser;

FIGURE 2 is a fragmentary side view of the lower end of the riser shown in FIG. 1;

FIGURE 3 is a horizontal section taken on the line 3 3 of FIG. 1;

FIGURE 4 is a horizontal section taken on the line 4 4 of FIG. 1 to further illustrate the telescoping arrangement between the upper and lower riser sections;

FIGURE 5 is a horizontal section taken on the line 5 5 of FIG. l to illustrate octagonal cross sections of the lower riser section and a radially expanded packing ring;`

FIGURE 6 is a horizontal section taken on line 6 6 of FIG. 1 to illustrate an roctagonal cross section of a ange on the seal;

FIGURE 7 is a side view of the seal illustrated in FIG. l; and

FIGURE 8 is a fragmentary vertical section taken on the line 8 8 of FIG. 2 to illustrate a stop on the lower section that engages the seal to assure that the seal can be reached with the upper riser section if the seal is disengaged inadvertently and slides to the bottom of the lower section.

Referring to the drawings, one station in a lawn sprinkler system is illustrated as comprising a vertical riser 10 having an upper pipe section 12 which is telescopic in a lower pipe section 14. A sprinkler head 16 threaded on the upper end of section 12 is disposed flush with the ground'. The lower section 14 is in the form of a T having ttings 16 disposed in opposite horizontal directions. Hoses 18 are connected on each .of the fittings 16 by clamps 20 to supply water to riser 10 an-d convey the water to other risers in the sprinkler system. Fittings 16 are joined integrally to an upstanding tubular portion 22 having an interior wall 24 fashioned with an octagonal transverse cross section. The octagonal cross section extends rom the top of section 14 to a radially inwardly directed projection or stepped shoulder 26 which is joined to a vertical passageway 28. Passageway 28 communicates with ttings 16.

The upper section 12 is also tubular and has a smooth round exterior surface. The outside diameter of section 12 is dimensioned relative to wall 24 so that section 12 is free to rotate and slide longitudinally when it is inserted in the lower section 14. A seal assembly 30 threaded in the Ilower end of section 12 releasably engages section 12 with section 14 and serves as a fluid seal. Section 12 extends upwardly through the upper end of section 14 and through a central aperture 32 in a cap 34 threaded on the upper end of section 14. Cap 34 is fashioned with a lip 36 which tapers upwardly and radially inwardly around the periphery of aperture 32. Lip 36 flts closely with section 12 to wipe and scrape section 12 during vertical adjustment of section 12 and thus minimize entry of dirt into the lower section. Without a close fit and good wiping action of lip 36, dirt and other foreign matter could be sucked into the lower section 14 due to a pumping action .of the seal assembly during vertical adjustment of section 12. Just below its threaded upper end, section 12 is fashioned with an integral hexagonal boss 33 which is used to hold section 12 with a wrench or the like while head 16 is screwed tightly in place.

The seal assembly 30 comprises a tubular post 44 having a longitudinal passageway 46 communicating between sections 12, 14. Post 44 is fashioned at its lower end with an integral radial flange 43 and at its upper end with male threads engaged in the lower end of section 12. The flange 48 has an o'ctagonal circumferential face 51 that mates with the octagonal wall 24 of the lower section 14 to prevent relative rotation between post 44 and section 14 while permitting movement of post 44 longitudinally in section 14. An annular packing ring 52 is disposed about post 44 abutting the upper face of flange 48. A pair of snap rings 54, are fastened aro-und post 44 between threads 50 and packing ring 52.

Ring 52 is formed of resilient rubber-like material such as neoprene so as to be radially expandible in response to axial compression. Ring 52 may have an axial dimension such that it must be compressed slightly in order to llt rings 54, 56 over post 44 below threads 5t) to eliminate any play between the parts of seal assembly 30. With retaining rings 54, 56 and packing ring 52 assembled on post 44, before -axial compression by section 12 ring 52 may engage wall 24 slightly, it at all, but does not appreciably restrain axial movement of the seal assembly 30 in the lower section 14. When the upper section 12 is threaded onto post 44, the lower end of section 12 engages ring 54 and as section 12 is tightened on post 44, rings 54, 56 move downwardly on post 44 compressing ring 52 to expand the ring into tight engagement with wall 24. Thus the vertical height of section 12 relative to section 14 may be adjusted by loosening section 12 to release ring 52 -from wall 24. Section 12 may then be adjusted telescopically to any desired height and tightened on post 44 to lock the upper section firmly in place on the lower section 14. As section 12 is tightened and loosened on post 44 there is no direct frictional contact between section 12 and packing ring 52. Radial expansion of ring 52 does not directly restrain rotation of the upper section 12 since the lower end of section 12 slides on ring 54 and ring 52 expands against post 44 which is nonrotatable. Moreover as ring 52 expands against post 44, ring 52 restrains rotation of post 44 to assist the keying action of face 51.

If section 12 is detached from seal assembly 30 inadvertently, the packing ring 52 remains on post 44 at all times with threads 50 easily accessible for engagement by section 12. Ring 52 is dimensioned axially and radially such that it, together with flange 48 and rings 54, 56, maintains post 44 in a centered position so that threads S0 can be easily re-engaged in the lower end of section 12. Should the seal assembly 30 drop to the lower end of the tubular portion 22, flange 48 will bottom on shoulder 26. The length of section 12 between its lower end and boss 38 is such that section 12 can be threadably engaged with post 44 in its lowermost position before lboss 38 bottoms on lip 36. The octagonal cross section of wall 24 and the mating octagonal face 51 on the flange 48 assure a nonrotatable engagement between the seal assembly 30 and the lower section 14. Additionally the octagonal wall 24 facilitates an effective seal between packing ring 52 andthe lowersection 14. Symmetry of the octagonal wall 24 evenly distributes radial forces on post 44 so that the post and the upper section 12 remain concentric with section 14 when the ring 52 is compressed.

In the preferred embodiment, sections 12, 14, cap 34, post 44 and rings 54, 56 are fabricated from a plastic material manufactured by The Hercules Powder Co. and sold commercially under the trade name Profax This material is economical to use and has characteristics that are particularly suited for lawn sprinkler systems.

It will be understood that the adjustable riser for sprinkler systems which is herein disclosed and described is presented for purposes of explanation and illustration and is not iitended to indicate limits of the invention, the scope of which is dened by the following claims.

What is claimed is:

1. A riser for use in an underground sprinkler system comprising a lower tubular riser section having an open upper end, an upper tubular riser section telescoped in said lower section for axial and rotational movement, means on the upper end of said lower section in sealing engagement with the external surface of the telescoped portion of said upper section, and a unitary securing and sealing assembly means for sealing said upper section in said lower section and for interengaging said upper and lower sections to restrain relative axial movement between said sections comprising a hollow post having a lower radial flange, said flange being keyed in said lower section for axial and nonrotatable movement therewith, a resilient packing ring disposed on said post above said flange, said ring tting closely and slidably in said lower section and in frictional contact therewith and being radially expansible in response to axial compression, external thread means on the upper end of said post above said ring, the o-uter diameter of said post between said threads and said flange being less than either the outer diameter of the threaded portion or the outer diameter of said flange, and a retaining ring having an inner diameter less than the outer diameter of said threads or said flange mounted on said post above said packing ring and below said thread means `for retaining said packing ring on said post, the lower end of said upper section having internal thread means mating with said thread means of said post and a radial shoulder on the lower end of said upper section engageable with said retaining ring when said upper section is threadedly engaged with said post to move sai-d retaining ring on said post against said packing ring and said packing ring against said lower radial flange and axially compress said packing ring thereby radially expanding said packing ring into sealing engagement with said po-st and said lower tubular riser section.

2. A riser for use in an underground sprinkler system comprising a lower tubular riser section, said lower section having an open upper end, an upper tubular riser section telescoped in said lower section for axial and rotatable movement, a cap releasably secured on the upper end of said lower section to close said open end and having an aperture therethrough, said upper section being slidable in said aperture, said cap having a lip defining the upper periphery of said aperture, said lip being tapered in a direction upwardly and inwardly of said cap and fitting closely on said upper section, and a unitary securing and sealing assembly means for sealing said upper section in said lower section and for interengaging said upper and lower sections to restrain relative axial movement between said sections comprising a hollow post having a lower radial flange, said flange being keyed in said lower section for axial and nonrotatable movement therewith, a resilient packing ring disposed on said post above said flange, said ring fitting closely and slidably in said lower section and in -frictional contact therewith and being radially expansible in response to axial compression, eX- ternal thread means on the upper end of said post above said ring, the outer diameter of said post between said threads and said flange being less than either the outer diameter of the threaded portion or the outer diameter of said flange, and a retaining ring having an inner diameter less than the outer diameter of said threads or said flange mounted on said post above said packing ring and below said thread means for retaining said packing ring on said post, the lower end of said upper section having internal thread means mating with said thread means of said post, and la radial shoulder on the lower end of said upper section engageable with said retaining ring when said upper section is threadedly engaged with said post to move said retaining ring on said pos-t against said packing ring and said packing ring against said lower radial flange and axially compress said packing ring thereby radially expanding said packing ring into sealing engagement with said post and said lower tubular riser section.

References Cited UNITED 2/1936 9/1953 lO/l960 4/1963 9/1964 2/1966 STATES PATENTS Bacigalupi 285-302 X Wayman 285-354 X Kotes 285-423 Hutty et al 285-302 X Gages 285-302 X Frank 285-45 X 10 EDWARD C. ALLEN, Primm Examiner.

D. W. AROLA, Assistant Examiner. 

1. A RISER FOR USE IN AN UNDERGROUND SPRINKLER SYSTEM COMPRISING A LOWER TUBULAR RISER SECTION HAVING AN OPEN UPPER END, AN UPPER TUBULAR RISER SECTION TELESCOPED IN SAID LOWER SECTION FOR AXIAL AND ROTATIONAL MOVEMENT, MEANS ON THE UPPER END OF SAID LOWER SECTION IN SEALING ENGAGEMENT WITH THE EXTERNAL SURFACE OF THE TELESCOPED PORTION OF SAID UPPER SECTION, AND A UNITARY SECURING AND SEALING ASSEMBLY MEANS FOR SEALING SAID UPPER SECTION IN SAID LOWER SECTION AND FOR INTERENGAGING SAID UPPER AND LOWER SECTIONS TO RESTRAIN RELATIVE AXIAL MOVEMENT BETWEEN SAID SECTIONS COMPRISING A HOLLOW POST HAVING A LOWER RADIAL FLANGE, SAID FLANGE BEING KEYED IN SAID LOWER SECTION FOR AXIAL AND NONROTATABLE MOVEMENT THEREWITH, A RESILIENT PACKING RING DISPOSED ON SAID POST ABOVE SAID FLANGE, SAID RING FITTING CLOSELY AND SLIDABLY IN SAID LOWER SECTION AND IN FRICTIONAL CONTACT THEREWITH AND BEING RADIALLY EXPANSIBLE IN RESPONSE TO AXIAL COMPRESSION, EXTERNAL THREAD MEANS ON THE UPPER END OF SAID POST ABOVE SAID RING, THE OUTER DIAMETER OF SAID POST BETWEEN SAID THREADS AND SAID FLANGE BEING LESS THAN EITHER THE OUTER DIAMETER OF THE THREADED PORTION OR THE THE OUTER DIAMETER OF SAID FLANGE, AND A RETAINING RING HAVING AN INNER DIAMETER LESS THAN THE OUTER DIAMETER OF SAID THREADS OR SAID FLANGE MOUNTED ON SAID POST ABOVE SAID PACKING RING AND BELOW SAID THREAD MEANS FOR RETAINING SAID PACKING RING ON SAID POST, THE LOWER END OF SAID UPPER SECTION HAVING INTERNAL THREADED MEANS MATING WITH SAID THREAD MEANS OF SAID POST AND A RADIAL SHOULDER ON THE LOWER END OF SAID UPPER SECTION ENGAGEABLE WITH SAID RETAINING RING WHEN SAID UPPER SECTION IS THREADEDLY ENGAGED WITH SAID POST TO MOVE SAID RETAINING RING ON SAID POST AGAINST SAID PACKING RING AND SAID PACKING RING AGAINST SAID LOWER RADIAL FLANGE AND AXIALLY COMPRESS SAID PACKING RING THEREBY RADIALLY EXPANDING SAID PACKING RING INTO SEALING ENGAGEMENT WITH SAID POST AND SAID LOWER TUBULAR RISER SECTION. 